مجلة بغداد للعلوم

A Scientific and Evaluated Journal Published by the College of Science for Women, University of Baghdad
Date of First issue(2004)
No.of Issue per year(4)
No.of papers per issue (25)
No. Of issue published between 2004-2017(60) issue
This Journal publish paper in Arabic and English in area of Biology, Chemistry, Physics, Mathematics and Computer.

The aqueous extract of banana fruits peal was tested for its effect on mitosis . The root tips of Allium cepa were used as plant test system and the bone marrow cells of the albino mice Mus musculus were used as mammalians test system in vivo .Root tips of Allium cepa were treated for four hours with five concentrations of the extract (5 , 10 , 20 , 40 ,60 mg / ml.).The Metaphase was arrested in all the treatments , the highest percentage ( 100 % ) was recorded in the first concentration , the last concentration caused stickiness and clumping of the chromosomes. The treatments did not cause significant difference in the mitotic index. The peals extract (5 mg /ml) was compared with the extracts of fruits bulb, leaves and roots of banana plant, it was found that the extract of fruits peal is the best considering the highest percentages of arrested Metaphase in the root tips cells. The albino mice Mus musculus were injected intraperitonial with the peals extract ( 0.01 , 0.02, 0.04, 0.06, 0.08 mg / gm body weight), the percentages of arrested Metaphase in the bone marrow of these animals were comparable to the recorded percentages when the animals were injected with colchicine ( 0.01 mg / gm b.w.) .This study revealed the antimitotic activity of the aqueous extract of banana fruits peal on both the plant and mammalian cells in vivo. Studies will be conducted to investigate the effect of the extract and its components on the proliferation of cancer cells in vitro and in vivo.

This study has been conducted to know the level of microbial ( bacteria and fungi) contamination in 5 types of biscuits from local markets of Baghdad city. Fifty samples (ten sample for each kind of biscuit) were studed,Two are local,others are Iranian,Turkish,and Holandies.
The following results have been achieved :
1. The highest number of bacteria was 21.6×103 cell/g in Iranian biscuit while the lowest number was 14.3× 103 cell/g in local biscuit No.1 . The highest number of fungi was 16×103 colony/g and the lowest number was 5.3×103 colony/g in the Iranian and the local biscuit No.1,respectively.
2. Staphylococcus aureus was the major bacteria appeared at highest level of 100% in Turkish biscuit. The lowest percentage was found in Hollandian biscuit with 37.28%. Bacillus cereus was the major bacteria with a percentage of 100% in local biscuit No.2 where as the lowest was in local biscuit No,1with a percentage of 20.93%, while it was not existed in Turkish biscuit. Esherichia coli was found in Hollandian biscuit at highest rate of 38.98% , the lowest value was appeared in Iranian biscuit with 28.16% while it was not exited in local biscuit No.1,2 and Turkish biscuit.
3. Aspergillus niger appeared at highest level of 66.66% in Hollandian biscuit, while was the lowest 37.73% in local biscuit No.1 and not existed in local biscuit No.2, The highest value of A.flavus was 69.76% in local biscuit No.2 and the lowest value in Hollandian biscuit in percentage 8.33%. It has not appeared in Iranian and Turkish biscuit. The A. terreus appeared at highest rate in Turkish biscuit with 33.33% , the lowest value was in local biscuit No.2 at 11.62% and was not appeared in Hollandian biscuit.The Penicillium spp. Was found at highest rate 25% in Hollandian biscuit , the lowest value of 9.52% was appeared in Turkish biscuit.

The present work aimed to study the effect of Grave's disease on the different tissues and organs of the body by using Wayne Thyrotoxicosis Diagnostic Index (WTDI) and Basel Metabolic Index (BMI).
To reach such aim, (35) patients were involved (25 females and 10 males). A control group of (15) healthy individuals (10 females and 5 males) was selected for comparison , as well as , the following:
1- Wayne Thyrotoxicosis Diagnostic Index (WTDI) applied on patient group and control group under the supervision of specialist medical team , this index include (19) sign and symptom , the appearance of one of them may be lead to the others. The sings and symptoms of the index appear only on the patients. There is no Significant differences between the replications of the sings and symptoms between the female patient and the male patients.
2- Basel Metabolic Index (BMI) applied on the patient group and control group , Significant decrease in the mean values of Basel Metabolic Index (BMI) was appeared in comparison with control group.

By- products of corn starch industry were used to prepare media for propagation the lactic acid bacteria as a natural auxotroph. The by- products used were the corn steep water (S) and gluten extract (G) after a proper treatment to get them ready for media preparation. The results showed that it was possible to replace the peptone and meat extract by gluten extract in MRS medium. The growth was approximately similar to that obtained in standard MRS media. Corn steep water (S) was used as well and the growth enhanced by including Tween – 80 at 1% level. The later media named MZ, which was superior for growing standard and local strains and starters. The MZ medium modified by adding acetate and glacial acetic acid similarly to Rogosa media and was very efficient selection property for selecting and growing of lactobacilli only. There was no difference in the starter activities grown in MRS or MZ liquid media used to coagulate sterile whole milk and the developed acidity was at similar extent.

The study was conducted during spring seasons of 2000 and 2001.The aim was to study the changes in the moisture content of sunflower plants during growth stages under hardening conditions to drought tolerance .Agricultural practices were made according to recommendation. Asplit-split plots design was used with three replications. The main plots included irrigation treatments:irrigation to100%(full irrigation),75and50%of available water. The sub plots were the cultivars Euroflor and Flame.The sub-sub plots represented four seed soaking treatments: Control (unsoaked), soaking in water ,Paclobutrazol solution(250ppm),and Pix solution(500ppm). The soaking continued for 24 hours then seeds were dried at room temperature until they regained their original weight. Amount of water for each irrigation were calculated to satisfy water depletion in soil using a neutron meter.
Results indicated that plant moisture content was not affected by irrigation treatments in both seasons and as a mean of seasons ,except after 72 days from planting in the season 2000.when stress 800 Kp caused a decreased in moisture content by 4.55and 5.18% compared with full irrigation and stress 600 Kp, respectively. Euroflor was superior over Flame after 30 days from planting by 13.64% in the season of 2000 and by 6.23% as a mean of seasons , and by 2.80% after 86 days from planting in the season of 2001.While Flame was superior by 2.75% after 58 days from planting in the season of 2001. Soaking in water , paclobutrazol and pix solutions increased plant moisture content by 4.56,3.92 and 3.82% after 86 days from planting in the season 2000 , soaking in water and paclobutrazol solution increased plant moisture content by 2.61 and 2.62% as amean of seasons compared with unsoaked treatment. In conclusion, soaking the seeds presowing in water or plant growth regulators could improve water relations of plants , and increase moisture content in plants tissues especially during flowering and seed filling , when the water requirements increased and associated with high temperature in spring season in Iraq.

The present study aims to identifying the effect of Eurygaster integriceps infection on the quality features of the local wheat varity IBA 99.
The result revealed significant decrease in the percentage of protein of infected wheat at (4, 5)% compared to sound wheat values for the sound wheat were (10.9%) whereas those for the infected wheat were(9.0, 8.4 )% also the result revealed significant increased in the percentage of ash in the infected wheat flour. The result showed significant decrease in the percentage of wet and dry gluten in the infected wheat by sun bug at the rate of (2, 3, 4, 5)% compared to sound wheat value (27, 9% and 25, 23, 22, 22, 20%) for wet gluten and (8.2, 7.8, 7, 7.2, 6%) for dry glutin .
The value of sedimentation of the infected wheat decreased as of the infection increased it reached 22 ml for sound wheat and (22, 20, 20, 17, 17,)ml for infected wheat at percentage (1, 2, 3, 4, 5)% respectively. The result of falling number test have also shown significant decreased as infection rate increased, it reached(330) for sound wheat and ( 322,307, 282, 260, 250)second for infected wheat at percentage (1, 2, 3, 4, 5)% respectively.
There were no significant different between the specific volume value of product loaf of infected wheat flour by sunn bug at percentage (1, 2, 3)% but the different were significant in specific volum value of infected wheat flour at rate (4 and 5)% compared to sound wheat. The sensitive evaluation of bread referred to no significant differences of quality and baking properties for loaf of infected wheat flour at (1, 2, 3,%) compared to sound wheat but the loaf of infected wheat flour at 4 and 5 % have low quality and baking properties compared to the loaf of sound wheat.

Five serological methods for detection of Brucella were compaired in this study, Four of the methods are commonely used in the detections:-
1-Rose-Bengal: as primary screening test which depends on detecting antibodies in the blood serum.
2-IFAT: which detects IgG and IgM antibodies in the serum.
3-ELISA test: which detects IgG antibodies in the serum.
4-2ME test: which detects IgG antibodies
The fifth methods. It was developed by a reasercher in one of the health centers in Baghdad. It was given the name of spot Immune Assay (SIA).
Results declares that among (100) samples of patients blood, 76, 49, 49, 37, and 28. samples were positive to Rose Bengal, ELISA, SIA, 2ME and IFAT tests, respectively.
When efficiency, sensitivity and specificity of the serological methods were compaired, the Following results were obtained:
a) ELISA and SIA were superiors among the other confirming methods (2ME and IFAT) in detecting the highest cases (49 cases); 46 of them were from the (76) cases positive to Rose Bengal The confirmatory test 2ME was not efficient in detecting low concentrations of IgG antibodies when less than half (37) of the total positive cases (76) were detected by this test.
b) IFAT test was the least efficient confirmatory test among all other test.
c) As a new confirmatory test, SIA proved to be an efficient and serological test for Brucella detection in comparison with other tests. It is an easy to use test, rapid and could be performed without need to the expensive equipment .

The study was conducted to identify the toxicity of chromium on scenedesmus quadricauda algae alone and in the presence of nutrient metal (Nitrogen). Different concentrations of chromium (0.5, 1.5 , 2.5, 3.5 , 4.5mg/L) were used and the presence nitrogen is (5 ,10 ,50 ,100mg/L) on cultur media(chu-10) with used for cultivation of the algae in controlled conditions(25oC , light intensity 380 –E/m2 /s. The results showed increasing in the toxicity of the metal when is alone , excess of concentrations an time of exposure. The growth rate decreased from 0.44 to 0.06 cell/ hour after 12 day of the biging of the experiment and of concentrate 4.5 mg/L of chromium.
The intermediate active concentrations of the chromium(EC50) was increased after 96 hours from the exposure, which it reached alevel at 3mg/L, which the increase of rate of inhibition which became 64, 80, 87 and 90% respectively with above mentioned concentrations of chromium. While after increasing the nitrogen concentrations in the culture media , an decrease was detected in the toxicity of the chromium at 3mg/L . Level through the increase in growth rate reached 0.30 cell /hour after the addition of 5mg/L of Nitrogen to the culture media which contain 3mg/L of chromium. This increase was also a companied by a decrease in rate of inhibition at a level of 74%, 69%, 78%, 70% respectively with the above mentioned treatment concentrations. From the above results it could be concluded that the toxicity of chromium may be declined under the effect of the Nitrogen

The study included studying some of the optimum environmental conditions(temperature ,light intensity ) on the production of several green algae Scendesmus quadricauda and Chlorella vulgaris in a selected culture and municipal wastewater . The study also included the recording of growth rate ,doubling time and removal of phosphate and nitrate , maximum rate was recorded to the growth with minimum in doubling time and maximum removal rate of nitrogen-nitrate and phosor- phosphate in each selected culture and municipal wastewater in each species of green algae at 25 Cْ and a light intensity 380 µ E / m2 / s.

This paper present a simple and sensitive method for the determination of DL-Histidine using FIA-Chemiluminometric measurement resulted from oxidation of luminol molecule by hydrogen peroxide in alkaline medium in the presence of DL-Histidine. Using 70l. sample linear plot with a coefficient of determination 95.79% for (5-60) mmol.L-1 while for a quadratic relation C.O.D = 96.44% for (5-80) mmol.L-1 and found that guadratic plot in more representative. Limit of detection was 31.93 g DL-Histidine (S/N = 3), repeatability of measurement was less that 5% (n=6). Positive and negative ion interferances was removed by using minicolume containing ion exchange resin located after injection valve position.

The digital camera which contain light unit inside it is useful with low illumination but not for high. For different intensity; the quality of the image will not stay good but it will have dark or low intensity so we can not change the contrast and the intensity in order to increase the losses information in the bright and the dark regions. .
In this search we study the regular illumination on the images using the tungsten light by changing the intensities. The result appears that the tungsten light gives nearly far intensity for the three color bands(RGB) and the illuminated band(L).the result depend on the statistical properties which represented by the voltage ,power and intensities and the effect of this parameter on the digital camera .

Bloch correction is considered one of the important corrections for stopping power for its ability to connect the classic description of the (Bohr) scientist with the quantum treatment of (Bethe) scientist.
In this research we made a study about considoving the Bloch correction a bout phase shift conditions and for different phases from particle energy and appeared that Bloch correction in its relativistic case and non- relativistic case that depend on phase shift condition and particle energy but in the Ultra relativistic case for Bloch correction that depend on phase shift condition only. We made electronic stopping power correction in low speed by using phase shift conditions .

The objective of the present work is to measuring the concentration of heavy elements (Pb, Cd, Zn, As) in Baghdad's soil city and indication to the probable sources of pollution as well as comparing the concentration of heavy elements with local and international ranges. The Sampling and analyzing conducted in the present work included ( 15 ) Samples from Baghdad city ( three samples for each location ).The rates of heavy elements in soil samples were as following:.
Pb ( 67.5 ) ppm, Cd ( 4.11 ) ppm , Zn ( 77.9 ) ppm , As ( 4.64 ) ppm. According to the results, we find increasing in the concentrations of the heavy elements ( Pb, Cd, Zn ) in soils and decreasing in ( As ).We conclude that the main reason behind the increasing of the concentrations of heavy elements in Baghdad city's soils is due to the anthropogenic activities like the domestic wastes, the products released from the combustion of fuel containing ( tetraethyl lead ), and the industrial wastes (solid , liquid and gaseous) especially from oil industries. Other important factor that added to the pollution with these heavy elements is the three successive wars that Iraq had subjected. The explosion of rockets and bombs contributed mainly to the pollution of soil.

This study presents the design of flash-lamps for pumped solid-state lasers. In this research have been study some of characters for flash lamp.
The optimum pressure operation is found using different flash lamps about (600-4000) mbar. In conclusion, it was shown that the increase in pressure due to improve efficiency of radiation and decrease of temperature. Also this study illustrated the reason of decrease temperature is atomic number and due to increase of radiation efficiency.

Sixteen Vibrio isolates producing L-glutaminase were obtained from clinical and water samples , one isolate was selected according to its’ highest enzyme productivity , it was identified as Vibrio cholerae (NAG) and coded as V. cholerae S1.
The bacteria was cultured in a liquid medium (containing L-glutamine) , L-glutaminase was extracted from the cells by ultrasonication , the enzyme was precipitated by 30 % saturation of ammonium sulphate , dialyzed and immobilized by adsorption on different supports including Sephadex G-100 , cellulose powder , starch , silica gel , glass beads and charcoal.
Sephadex G-100 retained most of enzyme activity (90 %) followed by starch (78 %) , then silica gel and cellulose powder (71 %) while glass beads and charcoal retained 58 % only.
The immobilized enzyme was subjected to different temperatures and pHs. The results showed that the immobilized enzyme is more stable than the free enzyme in different temperatures and pHs. Silica gel was the best matrix for protecting L-glutaminase against heat , it retained 52 and 22 % of the original activity after 2 hrs of incubation at 50 and 60 ۫c respectively while the free enzyme retained 30 and 10 % at the same conditions.
The immobilized enzyme was more stable at pH 7 than at pH 4 or 10 . the enzyme adsorbed on Sephadex G-100 retained the maximum activity (98 %) at pH 7 for 2 hrs , while it was 73 % for the free enzyme.
The immobilized L-glutaminase of V. cholerae S1 (with Sephadex G-100) was stored at 4 ۫c for 30 days , the remaining activity was 35 % , while it was 18 % for the free enzyme.
It can be concluded from these results that V. cholerae S1 L-glutaminase can be immobilized on different inert materials, Sephadex G-100 is more suitable in this project , Silica gel can protect the enzyme against heat. In general the immobilized enzyme is more stable at different temperatures , pH and time than the free enzyme.

The study included the extraction of volatile oil from Mentha piperita which was 1.3 % in the leaves and flowers . Volatile oil of the Mentha piperita leaves had special aromatic odour, pale yellow color, slightly pungent taste . The specific gravity and refractive index were (0.9794) and ( 1.464) respectively.
The inhibition activity of the Mentha piperita Volatile oil extracts were studied on some pathogenic microorganisms like Staphylococcus aureus, Salmonella typhi, Escherichia coli, Proteus sp, and Klebsiella pneumoniae . The result showed that the volatile oil had an inhibition effect on the growth of all microorganisms, and it gave the higher inhibition effect on the growth of S. aureus in which the inhibition zone reached to 25 mm. also the inhibition zoon on the growth of K. pneumoniae was 20 mm.and it was 17 mm. on the growth of Salmonella.typhi , while the effect was slight on the growth of Proteus sp and E. coli 12,10 mm. respectively.
The minimum inhibition concentration (MIC) and the minimum bactericidal concentration (MBC) of the volatile oil extract of the Mentha .piperita leaves, were determined. The value of (MIC, MBC) of Staph. aureus was 0.625 , 1.25 % and the value for (MIC, MBC) of K. pneumoniaeو Salmonella typhi were 1.25 , 2.5 % for each of them, while the value of (MIC, MBC) of Proteus sp , E. coli were 2.5 , 5 % respectively .

In this study, phytoplankton density, chlorophyll-a, and selected physico- chemical parameters were investigated in Erbil wastewater channel. The surveys were carried out monthly from May 2003 to April 2004. Samplings were established on three sites from headwaters to the mouth. The results showed that pH was in alkaline side of neutrality, with significant differences (P<0.05) between sites 1 and 3. TSS concentration decreased from site 1 toward site 2 (mean value, 80.15 to 25.79 mg.l-1). A clear gradual increase in mineral content (TDS) observed from site one of the channel towards the mouthpart. Soluble reactive phosphate has a concentration maximum mean value reached 48.4 µg.l-1 which is recorded in site 2. A high positive relationship (P<0.01, r =0.449) obtained between phosphate concentration and phytoplankton density. The results of chlorophyll-a concentration were (mean values, 2.26, 3.88 and 2.42 µg.l-1 respectively), showed the positive relationship (P<0.05, r =0.012) with phytoplankton density.
The PCA produced three significant main components which represented by more than 64.5% of the total variance, namely, nutrients related to algal productivity; disposal wastewater and storm water runoff, in which explained by 31.29, 19.68 and 13.55% respectively of the total variance of water quality in polluted channel.

The present work includes a study of viscosity of solutions containing Potassium Chloride and Potassium Bromide in Dimethyl Sulphoxide and water as solvent (containing 60% w/w DMSO).
The study was carried out at six different temperatures. The applicability of Jones- Dole equation has been discussed. Solute –solvent interaction was discussed in terms of ionic size, charge, and shape of solute molecules.

A rapid high sensitive and inexpensive economic method has been developed for the Determination of phenoxazine by using molecular spectrophotometry. The method is based on the oxidation of phenoxazine by potassium (meta)periodate in acidic medium.
The oxidation conditions were selected to enhance the sensitivity and the stability of the pink colored species which shows an absorption maximum at 530 nm. The Beer’s law was obeyed for phenoxazine concentration range from 1 to 6 µg mL-1 with 0.003 µg mL-1 detection limit and provided variation coefficients between 0.4 to 1.7 %. This method was successfully applied for the determination of phenoxazine in aqueous samples

A new Schiff base of 4- flourophenyl-4- nitrobenzyliden (L) ,was prepared and used to prepare a number of metal complexes with Cr (III) , Fe (III), Co(II) ,Ni (II) and Cu (II). These complexes were isolated and characterized by (FITR),UV-Vis spectroscopy and flame atomic absorption techniques in addition to magnetic susceptibility, and conductivity measurements. The study of the nature of the complexes formed in ethanol was done following the molar ratio method gave results, agreed with those obtained from isolated solid state studies. The antibacterial activity for the ligand and its metal complexes were examined against two selected microorganisms, Pseudomonas aeruginosa and Staphylococcus aureus.The results indicated that the complexes show the enhanced activity in comparison to the free ligand; these were attributed to the synergetic effect between the metal ion and the ligand in addition to the difference in the structural varieties.

An immunological technique was investigated for the detection of human semen in forensic analysis.This technique included a preparation of anti-human seminal plasma antibodies, by immunizing rabbits with treated human semen. The human semen was treated with an acid to prevent cross reactivity with other human body fluids. The antibody produced was tested against different animal,s seminal fluid samples (dog, goat ,sheep, cow) and human body fluids( saliva, blood , vaginal fluid, ear wax and human semen). It was found that using this developed technique was only selectively responsed with human semen .
The prepered kit was evaluated and tested in Forensic laboratory- Ministry of Health. Finally, results were obtained in a comparison with the recommended techniques.

An analytical expression for the charge density distributions is derived based on the use of occupation numbers of the states and the single particle wave functions of the harmonic oscillator potential with size parameters chosen to reproduce the observed root mean square charge radii for all considered nuclei. The derived expression, which is applicable throughout the whole region of shell nuclei, has been employed in the calculations concerning the charge density distributions for odd- of shell nuclei, such as and nuclei. It is found that introducing an additional parameters, namely and which reflect the difference of the occupation numbers of the states from the prediction of the simple shell model leads to obtain a remarkable agreement between the calculated and experimental results of the charge density distributions throughout the whole range of

Let f and g be a self – maps of a rational exterior space . A natural number m is called a minimal coincidence period of maps f and g if f^m and g^m have a coincidence point which is not coincidence by any earlier iterates. This paper presents a complete description of the set of algebraic coincidence periods for self - maps of a rational exterior space which has rank 2 .

Many of the key stream generators which are used in practice are LFSR-based in the sense that they produce the key stream according to a rule y = C(L(x)), where L(x) denotes an internal linear bit stream, produced by small number of parallel linear feedback shift registers (LFSRs), and C denotes some nonlinear compression function. In this paper we combine between the output sequences from the linear feedback shift registers with the sequences out from non linear key generator to get the final very strong key sequence

let H be an infinite – dimensional separable complex Hilbert space, and S be a multiplication semigroup of with 1. An operator T is called G-cyclic over S if there is a non-zero vector x H such that {Tn xS, n ≥0} is norm-dense in H. Bourdon and Feldman have proved that the existence of somewhere dense orbits implies hypercyclicity. We show the corresponding result for G-cyclicity.

The aim of this paper is to prove some results for equivalence of moduli of smoothnes in approximation theory , we used a"non uniform" modulus of smoothness and the weighted Ditzian –Totik moduli of smoothness in by spline functions ,several results are obtained .For example , it shown that ,for any the inequality , is satisfied ,finally, similar result for chebyshev partition and weighted Ditzian –Totik moduli of smoothness are also obtained.

Ciphers can be either symmetric-key or public-key. Symmetric-key ciphers are the most famous and important elements in many cryptographic systems. Individually, they provide confidentiality and privacy. The Aim of this paper is to Apply symmetric block ciphers algorithm which is called Tiny Encryption algorithm (TEA). There are many types of block cipher use different techniques and functions using basic arithmetic operations such as XOR, addition, subtraction, multiplication, bitwise shift, and division. TEA cipher uses XOR, addition and bitwise shift. The paper presents how a block cipher could be constructed in general, it includes an observation of the history, inventors, and algorithms of the TEA block ciphers. It also discuss the manner did the programming took in terms of modularity, simplicity, resource reservation, in the previous algorithm the user cannot enter the plain text as a characters, it must enter the ASCII cod of the characters we write a lot e of functions to solve this problem also we enable the user to save his message in text file to make him use it to receive a message from email ,Also the time of encryption and decryption are calculated to measure the performance of the algorithm., The implementation of TEA is made using C/C++ Borland compiler version( 4.5).

In this paper we present an operational computer vision system for real-time motion detection and recording that can be used in surveillance system. The system captures a video of a scene and identifies the frames that contains motion and record them in such a way that only the frames that is important to us is recorded and a report is made in the form of a movie is made and can be displayed. All parts that are captured by the camera are recorded to compare both movies. This serves as both a proof-of- concept and a verification of other existing algorithms for motion detection. Motion frames are detected using frame differencing. The results of the experiments with the system indicate the ability to minimize some of the problems false detection and missed detections (like in a sudden change of light in the scene). The software part is written in Matlab language as an M-file and using the Simulink library, the hardware part we used a Pentium 4 computer with a web camera or a laptop integrated camera.

In Automatic Speech Recognition (ASR) the non-linear data projection provided by a one hidden layer Multilayer Perceptron (MLP), trained to recognize phonemes, and has previous experiments to provide feature enhancement substantially increased ASR performance, especially in noise. Previous attempts to apply an analogous approach to speaker identification have not succeeded in improving performance, except by combining MLP processed features with other features. We present test results for the TIMIT database which show that the advantage of MLP preprocessing for open set speaker identification increases with the number of speakers used to train the MLP and that improved identification is obtained as this number increases beyond sixty. We also present a method for selecting the speakers used for MLP training which further improves identification performance.